Despite a greater accumulation of risk factors for at-risk drinking and alcohol use disorders, national epidemiological surveys consistently report that Blacks and Hispanics in the United States (US) have an comparable or lower prevalence of binge drinking and alcohol disorders compared to non-Hispanic Whites. However, mortality data indicate that they have higher rates of alcohol-attributable motor vehicle crash fatality (MVCF). These seemingly divergent patterns indicate an epidemiologic paradox, the consequences of which are important for public health: MVCF is a leading cause of death among young adults, Blacks and Hispanics experience substantial inequities in MVCF compared to non-Hispanic Whites, and approximately 30% of all MVCFs are alcohol-related. In the present application for a Mentored Research Scientist Development Award (K01), I propose to develop expertise in four areas that will allow me to develop a line of research into the racial/ethnic paradox in alcohol-related health: 1) Built environment effects on alcohol-related health; 2) Conceptualization and measurement of cultural and social norms regarding alcohol use; 3) Analysis of repeated measures data; and 4) Field methods in epidemiologic data collection. I will use the skills obtained in these training areas to begin to fill outstanding gaps in our understanding of racial/ethnic differences in alcohol- related health with three research projects, for which the K01 will allow me protected research time that would otherwise not be possible as a new assistant professor. First, I will probe the validity of the racial/ethnic paradox itself. I ill explore whether lower rates of problem drinking among racial/ethnic minorities are limited to adolescents and young adults, and whether rates of problem drinking among older adults are higher among Blacks and Hispanics compared to non-Hispanic Whites. This work will utilize a national longitudinal dataset and incorporate information on trajectories within Blacks and Latino subgroups, which have never been characterized. Second, I will determine if alcohol-related social norms mediate overall differences in alcohol use and MVC risk, adding to our knowledge of how the paradox arises. I will use data from the New York Social Environment Survey, an epidemiologic study in New York City with rich racial and ethnic diversity and one of the only community-based samples to measure alcohol norms. Third, I will test a potential mechanism to explain the racial/ethnic paradox: that Black and Hispanic individuals experience more alcohol-attributable MVCF because the built environment in which they consume alcohol is more dangerous (e.g., worse road conditions). To test this hypothesis I propose a novel study linking records from the Fatality Analysis Reporting System on a national level with census and land usage information. In addition to these research aims, my K01 award period will focus on preparation of an R01 grant proposal to collect original data on racial/ethnic differences in alcohol-related health that builds on and extends the research proposed here. These projects are feasible only if I have protected time for new training and research, which K01 funding will provide.